DIY Adjustable CV/CC Power Supply

Components required

The modules required for making this are pretty generic and can be found for pretty cheap at most of the major ecommerce retailers, here's the list:

• XL4015 Based Buck converter with CC/CV Trimmer Potentimeters

  • https://www.aliexpress.us/item/3256810052629213.html

  • https://www.amazon.com/Lithium-Battery-Charging-Converter-Charger/dp/B0DT17NX8H

  • Searching for "XL4015 CC CV Buck Converter" also works

• 0.28" Digital Voltmeter Ammeter Module, Even a Voltmeter module should be fine

  • https://www.aliexpress.us/item/3256810488267582.html

  • https://www.amazon.com/SHMZK-0-28-Digital-Voltmeter-Ammeter/dp/B0DWMRVZCH

  • Anything that fits the dimensions below should be good to go

• An LDO of your choice if you plan to give use a SMPS in the voltage ranges (28V-36V)

  • The 28V mark is due to the voltmeter/ammeter module's absolute max voltage rating

  • The 36V mark is for the Absolute max rating for XL4015 ICs

• Screws

  • 4x M1.4 or M1.6 are recommended, M2 is also possible if you want a really tight fit

  • 2x M3 for joining the top and bottom of the enclosure

The design is made in OnShape and is available at: https://cad.onshape.com/documents/41b74ae0d87d23d3c3c1d115/w/a168547a581522485e009f6e

The image above is a reference for assembling the power supply, currently the screws are supposed to be heated a little bit, then screwed directly into the plastic nibs that are present in design. For achieving a current measurement the leads must be in series, so You'll to scratch the copper and disconnect the OUT+ Plane and connect the Current leads in series.

Issues

• As this is not a proper Lab bench power supply, getting the CC value you set will not be possible without partially shorting the output, and changing the CC knob will not actively display the CC's limit.

• The current measurement is a bit hard to get working, since it involves scratching the pcb to disconnect the power planes